yes there is . I usually define it as recurring rate that is valid from jan 1 thru Dec 31, and give it lowest priority, like 1. I give mine the name "standard". So all other seasons you have defined with higher priorities will take precedence over default rate for their respective date periods. if there is not specific season defined for given period, it will use default "standard" rates. That way you do not have to define rates in gaps between seasons and also do not have to define it every year.
